No, that makes no sense, it's absurd
It was implied that the whirlpools were there to prevent anyone who wasn't supposed to reach it from stealing the Road Poneglyph.
by devouring the enemies who venture too close to his black ship.
If he were, we would have known from the moment his character was introduced, and it didn't happen that way
Gaban isn't the man with the burn scar, that theory is dead